This invention relates generally to electrical feedthrough systems and more particularly to such a system for pressurized containers.
In the electrical art it is frequently necessary to make electrical connections from the outside to the inside of containers which are either sealed, pressurized or liquid filled. Common practice, where moderate to high voltages are concerned, has been to utilize glass type headers.
A glass header consists of one or more metal conductors sealed in glass with ends extending from the glass for connection with circuit leads. The conductor material is required to have a coefficient of thermal expansion near that of the glass.
The glass in the header is bonded to a washer-like flange which is formed of a material having the proper thermal expansion coefficient but which also must be compatible for being affixed to the container by soldering, gluing or similar process.
Once in place, the glass header or feedthrough is rigid and subject to damage from handling or vibration and difficult to remove and replace. Additionally, it is not infrequent that the glass will break from high temperatures involved in the installation process.
Accordingly, occasions have arisen where the cost of headers, their repair and replacement, as well as time lost, is equal to or exceeds the cost of the entire system of which they are a part.
Therefore, to solve deficiencies found in the glass header used as a means of electrical feedthrough for containers, the following simplified system is presented.